1. Field of the Invention
The present invention relates to a portable wireless terminal, and more particularly to a hinge module for a portable wireless terminal.
2. Description of the Related Art
Generally, portable wireless terminals (terminals) can be classified according to their shape. For example, there are bar type terminals, flip type terminals and folder type terminals.
The bar type terminals are configured as a single body housing, and comprise data inputs and outputs, and receiver and transmitter modules. In the case of the bar type terminals, there is a disadvantage in this configuration, since a keypad used as data input means is always exposed to the outside, thereby causing the keypad to malfunction. In addition, the bar type terminals have a limit in their miniaturization due to a required minimal distance between the receiver and transmitter modules.
The flip type terminals generally comprise a terminal body, a flip cover, and a hinge module adapted to rotatably couple the flip cover to the terminal body. The terminal body is mounted with data inputs and outputs, and receiver and transmitter modules. The flip cover serves to cover a keypad used as data input means, thereby preventing malfunctioning of the keypad as in the bar type terminal. However, the flip type terminals also have a limit to their miniaturization due to the required minimal distance between the receiver and transmitter modules.
The folder type terminals generally comprise a terminal body, a folder, and a hinge module adapted to rotatably couple the folder to the terminal body. The folder type terminal is thereby opened or closed by the rotation of the folder relative to the terminal body. In a folded state, wherein the folder is in contact with the terminal body, the portable wireless terminal is in a call waiting mode thereby preventing malfunction of the keypad as a data input, since the keypad is mounted on the terminal body. Furthermore, when the folder type terminal is rotated from a folded position to an open position, the portable wireless terminal enters the conversation mode. This “unfolding” provides sufficient distance between the transmitter and receiver modules, thereby allowing miniaturization of the terminal. For these reasons, folder type terminals have increased in popularity.
In the flip type or folder type terminal the hinge module is adapted to rotatably couple the flip cover or folder to the terminal body. In these two terminal types, when the flip cover or folder is opened away from the terminal body in excess of a predetermined angle the hinge module is configured to cause the flip cover or folder to be forced towards its open position, without requiring any additional external force if, however, the flip cover or folder is opened below the predetermined angle, the flip cover or folder is forced to come into close contact with the terminal body (i.e., it is pre-disposed to shut when opened below a certain angle).
The conventional hinge module for use in the flip type or folder type portable wireless terminals is disclosed in U.S. Pat. No. 6,292,980, issued to Yi et al. on Sep. 25, 2001, the entire contents of which are incorporated herein by reference. The disclosed hinge module, comprises a hinge cam and hinge shaft, which are formed with mountain-shaped portions or valley-shaped portions, respectively, and a hinge spring received in a hinge housing and adapted to urge the hinge cam to come into close contact with the hinge shaft. In this case, the hinge module is designed to open and close a flip cover or folder of a portable wireless terminal by means of the mountain-shaped and valley-shaped portions and by means of elastic force of the hinge spring for urging the mountain-shaped portions to come into close contact with the valley-shaped portions.
Although the number of functions of the portable wireless terminals has rapidly increased as mobile services have become increasingly diversified, the conventional hinge module retains the simple function of causing the flip cover or folder of the portable wireless terminal to be opened away from, or closed to, the terminal body. This functionality limits modification of the specifications of the portable wireless terminals. For example, there are limitations to the addition of certain devices to the terminals for utilizing various mobile services. In addition to the limitations of specification and design of the terminals, the conventional hinge module has an additional disadvantage in that it cannot satisfy diverse customers' tastes and increasingly diversified mobile services.